Abstract: A method for preparing liposomes containing at least one nucleic acid encapsulated therein comprising the following steps: (A) mixing a gel or a liquid containing gel particles with aqueous medium Z1 to directly form the liposomes containing the at least one nucleic acid encapsulated therein; (B)(i) mixing a gel or a liquid containing gel particles with aqueous medium Z1 to form a curd or curdy substance; and (ii) mixing the curd or curdy substance with aqueous medium Z2 to directly form the liposomes containing the at least one nucleic acid encapsulated therein; or (C)(i) cooling a gel or a liquid containing gel particles to form a waxy substance; and (ii) mixing the waxy substance with aqueous medium Z1 to directly form the liposomes containing the at least one nucleic acid encapsulated therein; wherein said gel or liquid containing gel particles comprises at least one liposome-forming lipid, at least one fusogenic lipid, a water-miscible organic solvent and the at least one nucleic acid; wherein an amount